Cup Plant or Prairie Dock or Rosin Wood
Erect clump forming plants that are hairless with leaves that rap around the thick-square stems to form little tubs were water collects and birds can get a drink. Finches feed on the nutritious seeds in late fall and winter. In midsummer and early fall Silphium perfoliatum produces large open branched corymbs like inflorescence with 50 to 100+, 2 to 3 in yellow daisy like flowers. Silphium perfoliatum grows from 6-10 feet tall and 3-4 feet wide. Plants like a moister soil than other species but do very well in my drier sunny garden with some light watering during very dry periods. Long lived and appealing-plant in the prairie garden or the back of the border, or plant in the open woodland garden. Loved by butterflies and honey bees.
Native from all the states east of the Rocky Mountains except Texas and Florida. This species is becoming very rare in the wild and is on the threatened species list for the state of Michigan. Cover with moist seed mix and use 12 weeks at 30-39F, move to 65-75F for Germination, or sow and place outside in a sheltered location in the fall for Germination in the spring.